Mammary Adenocarcinoma Associated with Uterine Leiomyoma and Osseous Metaplasia in New Zealand Rabbit-A case Report

Eatelaf Abdulameer Al-Mutheffer; Omar   Khalaf; Raffal  Omar; Zahraa Abbas; Zainab Fadhal; Yvonne  Reinwald

doi:10.30539/vpd0yd72

Authors

Eatelaf A. Al-Mutheffer College of Veterinary Medicine, University of Baghdad https://orcid.org/0000-0002-3167-7116
Omar H. Khalaf College of Veterinary Medicine at the University of Baghdad https://orcid.org/0000-0001-9793-7921
Raffal A. Omar College of Veterinary Medicine, University of Baghdad. https://orcid.org/0000-0003-4499-8100
Zahraa A. Abbas College of Veterinary Medicine, University of Baghdad https://orcid.org/0009-0004-5172-1307
Zainab Fadhal School of Medicine, University of Leeds, Leeds, United Kingdom https://orcid.org/0009-0007-1246-5701
Yvonne Reinwald School of Science and Technology, Nottingham Trent University https://orcid.org/0000-0001-6733-605X

Keywords:

adenocarcinoma‎, leiomyoma, osseous metaplasia, mammary gland, uterine, tumours, elderly rabbit

Abstract

A nine-year-old female indoor New Zealand breed pet rabbit was presented to the Department of Surgery and Obstetrics with a prominent mass in the left fourth mammary gland. The animal was not spayed and was not exposed to the breeding cycle. The animal was initially admitted for surgical excision of the mass. The patient then underwent an elective ovariohysterectomy, which identified another lesion within the ovaries and uterus. The pet rabbit underwent two successful surgeries to remove lesions. The postoperative recovery period was uneventful, and the animal remained in good health for approximately six months. After this period, the animal developed signs of acute respiratory distress, which resulted in its death within a short time from the onset of symptoms. The excised mammary mass, ovaries, and uterine tissue, along with post-mortem samples from the lungs, kidneys, and liver that were collected after the pet's death, were preserved in cold physiological saline and sent for histopathological evaluation. The macro examination during the mammectomy revealed a 3 × 2 × 2 cm dark-red, firm, multilobulated subcutaneous mass arising from the left fourth abdominal mammary gland. On sectioning, the mass showed grey-tan multinodular solid tissue supported by fibrous stroma. The microscopic examination revealed a primary invasive mammary adenocarcinoma (Grade II), with metastases (Stage IV) in most internal organs, such as the lung, kidney, and liver. Concurrently, uterine leiomyoma, osseous metaplasia of the uterine wall with cystic endometrial hyperplasia have also been reported. This report describes a rare coexistence of mammary adenocarcinoma and uterine leiomyoma and osseous metaplasia in a rabbit. It emphasizes the importance of the full assessment of the reproductive system in aged, female rabbits that are not spayed with mammary gland tumours‎‎‎.

Received: XX April 2026

Revised: XX August 2026

Accepted: XX August 2026

Published: Online First

Author Biographies

Eatelaf A. Al-Mutheffer , College of Veterinary Medicine, University of Baghdad

E'Atelaf Abdul-Ameer Al-Mutheffer: Doctor of Philosophy from ISTM / Keele University

Assisstant professor at Baghdad University College of veterinary medicine Biomaterials in veterinary orthopedics

She is a professional veterinary surgeon and small animals surgery assistant professor in the College of veterinary medicine at Baghdad University with great experience in veterinary surgery. Previously worked at the Institute for Science and Technology in Medicine, Keele University research in Medical Technology, Orthodontics, Cell biology, and tissue engineering. Her current research is in veterinary orthopaedics.

Omar H. Khalaf , College of Veterinary Medicine at the University of Baghdad

Dr. Omar H. Khalaf, a lecturer and researcher in the College of Veterinary Medicine at the University of Baghdad. He holds a PhD and is noted for his work in veterinary pathology and contributions to scientific research.

Raffal A. Omar , College of Veterinary Medicine, University of Baghdad.

Raffal A. Omar is an Assistant Professor/Professor in the Department of Physiology, Biochemistry, and Pharmacology at the College of Veterinary Medicine, University of Baghdad. She specializes in veterinary research, including anesthetics, pharmacology, and animal science, and is listed in academic databases like Google Scholar, ResearchGate, and AD Scientific Index.

Zahraa A. Abbas , College of Veterinary Medicine, University of Baghdad

A Veterinarian employed in Department of Surgery and Obstetrics, College of Veterinary Medicine, University of Baghdad

Zainab Fadhal , School of Medicine, University of Leeds, Leeds, United Kingdom

2021-09 to present | Medical student (School of Medicine 4 th year ) Employment National Health Service: London, England, GB

Yvonne Reinwald , School of Science and Technology, Nottingham Trent University

Dr Yvonne Reinwald is Lecturer in Biomedical Engineering.

Prior to joining NTU Dr Yvonne Reinwald worked at the Institute for Science and Technology at Keele University, where she carried out research in regenerative medicine. She also taught cell biomechanics, bioreactors and biomaterials in tissue engineering.

In 2016, Dr Reinwald was awarded Robert Brown Early Stage Investigator Award of the Tissue and Cell Engineering Society in 2016. Dr Reinwald’s research focuses on the evaluation of the performance of bioreactors for tissue engineering and clinical application by investigating the growth environment that cells and cell-constructs are exposed to during mechanical stimulation. She also has an interest in characterisation of biomedical implants for the assessment of quality control criteria aiding manufacture and clinical translation.

Professional Societies: Tissue Engineering & Regenerative Medicine International Society, The Tissue and Cell Engineering Society, Institute for Physics and Engineering in Medicine

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